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111.
Several studies indicate that local immunoregulation and associated cytokines have a putative role in the development of cancer. There is evidence that pro-inflammatory cytokines such as interleukin-1 (IL-1) are critically involved with tumour progression. IL-1 receptor antagonist (IL-1Ra) is known to down-regulate and limit the inflammatory response. Therefore we attempted to examine the influence of the known polymorphism of the IL-1Ra gene on the development of human colorectal cancer (CRC). The study included 125 patients with CRC and 134 controls. Variable number tandem repeat (VNTR) polymorphism in intron 2 of the IL-Ra gene was analysed by the polymerase chain reaction method. There was a significant difference in genotype distribution between CRC patients and controls (P=0.025) and also in allelic frequencies (P=0.012). In detail the carriage rate of allele 3 in CRC patients was significantly increased compared with controls (P=0.007). We also found that the allelic distribution differs significantly between colon and rectum (P=0.041) and that allele 3 was overabundant in colon. The frequency of allele 1 in CRC patients with localized disease (Dukes A+B) was higher compared with disseminated disease (Dukes C+D), (P=0.035). These findings therefore suggest that the IL-1Ra polymorphism is associated with colorectal carcinogenesis.  相似文献   
112.
Thirty-eight testicular hydroceles were treated by injection with 0.2–0.4 g of bismuth phosphate. The follow-up was completed in 32 cases, 17 (53%) of which showed complete regression although one patient had to wait 24 months for full regression. Eight patients (25%) showed clinical improvement and one patient (3%) had residual scrotal tenderness after otherwise successful treatment. Six patients (19%) did not improve and were treated surgically. The method may present an alternative to surgery in elderly patients with testicular hydrocele.  相似文献   
113.
ATP binding cassette A1 (ABCA1) is involved in the lipid metabolism of macrophages and has been suggested to play an important role in the development of foam cells and in the pathogenesis of atherosclerosis. We have investigated the effects of all-trans retinoic acid (atRA) on the mRNA and protein levels of ABCA1 in THP-1 cells. Our results show that both mRNA and protein levels of ABCA1 were significantly increased upon treatment with atRA. Since ABCA1 is highly regulated by liver X receptor (LXR) we also analysed the mRNA and protein expressions of LXR-alpha and LXR-beta in the THP-1 cells after treatment with atRA. Also the levels of LXR-alpha were increased by atRA. In conclusion, our results show that LXR-alpha and ABCA1 are simultaneously induced by atRA. The results also imply that the induction of ABCA1 by atRA may in part depend on the induction of LXR.  相似文献   
114.
Objectives: Following up on two earlier publications showing increased psychological stress and psychosocial effects of travel on the business travellers this study investigated the health of spouses of business travellers. Methods: Medical claims of spouses of Washington DC World Bank staff participating in the medical insurance programme in 1997–8 were reviewed. Only the first of each diagnosis with the ninth revision of the international classification of diseases (ICD-9) recorded for each person was included in this analysis. The claims were grouped into 28 diagnostic categories and subcategories. Results: There were almost twice as many women as men among the 4630 identified spouses. Overall, male and female spouses of travellers filed claims for medical treatment at about a 16% higher rate than spouses of non-travellers. As hypothesised, a higher rate for psychological treatment was found in the spouses of international business travellers compared with non-travellers (men standardised rate ratios (RR)=1.55; women RR=1.37). For stress related psychological disorders the rates tripled for both female and male spouses of frequent travellers (≥ four missions/year) compared with those of non-travelling employees. An increased rate of claims among spouses of travellers versus non-travellers was also found for treatment for certain other diagnostic groups. Of these, diseases of the skin (men RR=2.93; women RR=1.41) and intestinal diseases (men RR=1.31; women RR=1.47) may have some association with the spouses'' travel, whereas others, such as malignant neoplasms (men RR=1.97; women RR=0.79) are less likely to have such a relation. Conclusion: The previously identified pattern of increased psychological disorders among business travellers is mirrored among their spouses. This finding underscores the permeable boundary between family relations and working life which earlier studies suggested, and it emphasises the need for concern within institutions and strategies for prevention.  相似文献   
115.
Deep venous thrombosis associated with corporate air travel   总被引:1,自引:0,他引:1  
BACKGROUND: Deep venous thrombosis (DVT) is commonly seen among bedridden and postoperative patients. Its association with travel may also make DVT an occupational health risk to otherwise healthy business travelers. We estimated the incidence of and risk factors for DVT among 8,189 World Bank employees and a subset of 4,951 international business travelers. METHODS: Occurrence of DVT between 1995 and 1998 was determined using 1) medical insurance claims; 2) Workers' Compensation claims; and 3) intra-office E-mail solicitation followed by interview. For each insurance claim case, 10 controls were randomly selected from among World Bank employees insured during the same month and year as the case's claim was filed, and case-control analyses were performed to identify potential predictors or risk factors for DVT. RESULTS: Thirty individuals filed claims for DVT of the legs (annual incidence rate: 0.9 per 1,000 employees); three of these claims were filed within 30 days after a travel mission. Two employees reported DVT as a Workers' Compensation injury, and five staff with verified DVT participated in interviews. After controlling for age and gender, no association with any travel-related covariate was seen. Results of analyses considering all thrombophlebitis and thromboembolism followed the same pattern. The average annual incidence of DVT occurring within 30 days of mission among traveling staff ranged from 0.10 per 1,000 to 0.25 per 1,000 travelers, depending on the case-finding method. CONCLUSION: No association between DVT and travel was observed after adjustment for gender and age. These results, however, are preliminary, and due to the rarity of DVT, based on small numbers.  相似文献   
116.
The function of NGF in chick embryos was studied by injecting antibodies to mouse nerve growth factor (NGF). The uptake of mammalian antibodies into the 8- to 15-day-old chick embryo was followed by an enzyme-linked immunoassay. Normal rabbit antibodies (250 μg) were administered to the yolk, of which less than 5% was found in the embryo (300 ng of IgG per g wet wt of embryo). The concentration was proportionally lower when 100 μg anti-NGF antibodies were injected (40 ng/g). The concentration of anti-NGF antibodies was 1.5 times higher following injection directly into the body of the embryos. The effects of injecting antibodies at days 3–7 were studied in 10-day-old embryos by measuring the diameter frequencies of neurons in sympathetic and sensory ganglia. In comparison with controls, significantly smaller neurons were found in the sympathetic ganglia in embryos directly injected with anti-NGF. In the spinal ganglia, distribution of neuron diameters did not differ between anti-NGF-treated embryos and controls. Finally, the ability of different antibodies to mouse NGF to inhibit the in vitro activity of recombinant chick NGF was investigated. Total block was found at 1000–2000 ng of IgG per ml for most of the antibodies tested, levels not reached when injecting the embryo with antibodies to NGF. We conclude that the main reason for the limited effects in chick embryos by injection of NGF antibodies is due to the low levels of penetration of the anti-NGF IgG into the embryo.  相似文献   
117.
Facial reactions to fear-relevant and fear-irrelevant stimuli   总被引:1,自引:0,他引:1  
Earlier research has shown that subjects exposed to different facial expressions react spontaneously with different facial electromyographic (EMG) response patterns. In the present study subjects were exposed to fear-relevant (snakes/spiders) and fear-irrelevant (flowers/mushrooms) stimuli, while facial EMG activity, skin conductance responses (SCRs) and heart rate (HR) were measured. The stimuli evoked different response patterns. Fear-relevant stimuli elicited increased corrugator muscle activity, whereas fear-irrelevant stimuli evoked increased zygomatic muscle activity. Fear-relevant stimuli also evoked HR deceleration and larger SCR magnitudes. The present data are consistent with the theory that the face constitutes an emotional 'readout/output-system'.  相似文献   
118.
People with specific animal phobias react with increased autonomic activity when exposed to fear-relevant stimuli. The present study examined whether individuals having a less circumscribed fear (public speaking fear) also react with increased autonomic responses when exposed to fear-relevant i.e. social stimuli. A High-fear and a Low-fear group, as indicated by the PRCS questionnaire, were exposed to pictures of faces (social stimuli) and mushrooms (neutral stimuli) while heart rate (HR) and skin conductance responses (SCRs) were measured. It was found that: Social stimuli evoked larger SCRs as compared to neutral stimuli only in the High-fear group; SCR magnitude to social stimuli was positively correlated with self-reported fear in the High-fear group; the High-fear group showed larger overall SCRs compared with the Low-fear group; the High-fear group showed slower SCR habituation to social stimuli as compared to the Low-fear group; the High-fear group displayed more nonspecific electrodermal fluctuations than did the Low-fear group. Both the High-fear and the Low-fear group displayed HR deceleration to social but not to neutral stimuli. Thus, subjects high in public speaking fear reacted with increased skin conductance activity when exposed to social stimuli compared to low-fear subjects. The two groups did not differ in heart rate responses. These results are discussed in terms of orienting, defense and species-specific response patterns.  相似文献   
119.
Objective:To follow a group of children from primary to early permanent dentition and determine the prevalence, self-correction, and new development of malocclusions; the need for orthodontic treatment; and the possible influences of habits, breathing disturbances, and allergies.Materials and Methods:Two hundred and seventy-seven children were followed at 3, 7, and 11.5 years of age. Malocclusions and orthodontic treatment need were determined by clinical examinations. Data on sucking habits, breathing disturbances, allergies, dental trauma, and orthodontic treatments were collected from a questionnaire and dental records.Results:Malocclusions were found in 71% of participants at 3 years of age, 56% at 7 years of age, and 71% at 11.5 years of age. Self-correction was noted for anterior open bite, sagittal malocclusions, and posterior crossbite, while deep bite developed. A high number of contact point displacements and spacings contributed to the prevalence of malocclusion rate of 71% at 11.5 years. Severe or extreme orthodontic treatment need was apparent in 22%. Habits, allergies, or breathing disturbances found at 3 years of age had no associations with malocclusions at 11.5 years of age.Conclusions:This sample revealed a significant percentage of malocclusions and orthodontic treatment need. A substantial number of self-corrections and establishment of new malocclusions occurred during the transition from primary to early permanent dentition.  相似文献   
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